Variance and Passivity Constrained Fuzzy Control for Nonlinear Ship Steering Systems with State Multiplicative Noises

The variance and passivity constrained fuzzy control problem for the nonlinear ship steering systems with state multiplicative noises is investigated. The continuous-time Takagi-Sugeno fuzzy model is used to represent the nonlinear ship steering systems with state multiplicative noises. In order to simultaneously achieve variance, passivity, and stability performances, some sufficient conditions are derived based on the Lyapunov theory. Employing the matrix transformation technique, these sufficient conditions can be expressed in terms of linear matrix inequalities. By solving the corresponding linear matrix inequality conditions, a parallel distributed compensation based fuzzy controller can be obtained to guarantee the stability of the closed-loop nonlinear ship steering systems subject to variance and passivity performance constraints. Finally, a numerical simulation example is provided to illustrate the usefulness and applicability of the proposed multiple performance constrained fuzzy control method

Variance-constrained multiobjective control and filtering for nonlinear stochastic systems: A survey

The multiobjective control and filtering problems for nonlinear stochastic systems with variance constraints are surveyed. First, the concepts of nonlinear stochastic systems are recalled along with the introduction of some recent advances. Then, the covariance control theory, which serves as a practical method for multi-objective control design as well as a foundation for linear system theory, is reviewed comprehensively. The multiple design requirements frequently applied in engineering practice for the use of evaluating system performances are introduced, including robustness, reliability, and dissipativity. Several design techniques suitable for the multi-objective variance-constrained control and filtering problems for nonlinear stochastic systems are discussed. In particular, as a special case for the multi-objective design problems, the mixed H 2 / H ∞ control and filtering problems are reviewed in great detail. Subsequently, some latest results on the variance-constrained multi-objective control and filtering problems for the nonlinear stochastic systems are summarized. Finally, conclusions are drawn, and several possible future research directions are pointed out

Robust Control of Delayed Fin Stabilizer Stochastic Systems of a Ship

In this paper, the robust control problem of delayed fin stabilizer stochastic system of a ship with uncertainty is discussed and investigated. To describe the system, Linear Parameter Varying (LPV) modelling approach and multiplicative noise term are used to establish the corresponding polynomial model. For simulating the general operating environment, the delay effect is considered as time-varying case. Moreover, the gain-scheduled control scheme is employed to discuss the delay-dependent stabilization problem and to design the corresponding controller. Moreover, a novel Lyapunov-Kravoskii function is proposed by using parameter-dependent matrix and integral Lyapunov function to reduce the conservatism of the derived stability conditions. In order to apply the convex optimization algorithm, the derived conditions are converted into Linear Matrix Inequality (LMI) form. By solving the conditions, some feasible solutions can be obtained to establish the controller to guarantee robust stability of the delayed fin stabilizer stochastic system of a ship in the mean square

Design of Congestion Control Scheme for Uncertain Discrete Network Systems

For a class of uncertain discrete network systems, a sliding mode control algorithm is presented for active queue management (AQM) in order to solve the problem of congestion control in transmission control protocol (TCP) communication. First, the sliding surface is designed based on linear matrix inequality (LMI) technique. Then, we analyze the mechanism of chattering for the discrete-time exponential approximation law, a modified one is presented and applied to the network systems. Simulation results demonstrate that the proposed controller has good stability and robustness with respect to the uncertainties of the number of active TCPsessions, link capacity and the round-trip time

Super-Twisting-Algorithm-Based Terminal Sliding Mode Control for a Bioreactor System

This study proposes a class of super-twisting-algorithm-based (STA-based) terminal sliding mode control (TSMC) for a bioreactor system with second-order type dynamics. TSMC not only can retain the advantages of conventional sliding mode control (CSMC), including easy implementation, robustness to disturbances, and fast response, but also can make the system states converge to the equivalent point in a finite amount of time after the system states intersect the sliding surface. The chattering phenomena in TSMC will originally exist on the sliding surface after the system states achieve the sliding surface and before the system states reach the equivalent point. However, by using the super twisting algorithm (STA), the chattering phenomena can be obviously reduced. The proposed method is also compared with two other methods: (1) CSMC without STA and (2) TSMC without STA. Finally, the control schemes are applied to the control of a bioreactor system to illustrate the effectiveness and applicability. Simulation results show that it can achieve better performance by using the proposed method

Event-Triggered Static Output Feedback Simultaneous H∞ Control for a Collection of Networked Control Systems

This chapter considers the design of event-triggered static output feedback simultaneous H∞ controllers for a collection of networked control systems (NCSs). It is shown that conventional point-to-point wiring delayed static output feedback simultaneous H∞ controllers can be obtained by solving linear matrix inequalities (LMIs) with a linear matrix equality (LME) constraint. Based on an obtained simultaneous H∞ controller, an L2-gain event-triggered transmission policy is proposed for reducing the network usage. An illustrative example is presented to verify the obtained theoretical results